One of the factors that decreases cycle life in lithium- (or other alkali metal- or alkali earth metal-) based batteries is the consumption of electrolyte during cycling of the battery due to reaction of metallic lithium present in the electrodes with the electrolyte. In order to minimize, or substantially prevent, this reaction and consequently increase the cycle life of the cell, it is desirable to isolate the metallic lithium from the electrolyte. This often times involves the use of a lithium ion conductive material layer coated on the surface of the metallic lithium. This material allows lithium ions to diffuse to and from the metallic lithium surface while excluding the electrolyte from contacting the lithium surface, therefore preventing any side reactions between lithium and the electrolyte. Although certain protective structures have been fabricated, improvements in the protective structures for lithium and other alkali metal electrodes would be beneficial and would have application in a number of different fields involving the use of such batteries and electrodes.